THE SHOULDER - ABDOMINAL CONNECTION TO BACK PAIN

Or The Sad Case of A Patient Hurting His Back While Doing Up His Trousers.

Donald McDowall, DC, MAppSc, DIBAK, FACC

4 Weedon Close Belconnen, ACT. Australia, 2617

ABSTRACT:

The strain between the interdigital connecting fibres of the serratus anticus (SA) andthe external oblique abdominus (EOA) muscles can cause back pain that can bediagnosed with manual muscle testing (MMT) and resolved using AppliedKinesiology (AK) muscle strengthening skills with rapid results and efficient patientoutcome. The anatomy, function, dysfunction and treatment of this strain arediscussed, illustrated and demonstrated. A case study is presented to illustrate thisphenomenon and its resolution.

INTRODUCTION:

The lower attachments of the origin of the serratus anticus muscle may be overlookedin the search for the cause of shoulder instability. Understanding the interdigitalfasiculae connection of this muscle with the external oblique abdominus provides anadditional link for creating more stability for the shoulder.

Shoulder problems are an enigma for many clinicians with difficult problems oftenresulting in prolonged physiotherapy or expensive surgery.(1,2) The case presentedgives an interesting indication of the involvement of shoulder instability with backpain.

The first muscle tested by George Goodheart in 1964 was the serratus anticus. (3)Goodheart observed the winging of the scapula in a patient he was treating for athyroid condition. The patient responded well to treatment for the thyroid conditionbut complained about the shoulder problem that Goodheart had struggled to fix.

Kendall’s book Muscle Testing and Function provided a method for Goodheart toobserve and diagnose muscle impairments in the shoulder. Instead of using physicaltherapy exercises for treatment Goodheart palpated nodules observed at the origin ofthe muscle tendon attachments on the ribs. The act of palpation caused the serratus tocontract much to Goodheart’s surprise. The correction of the flared scapula wasremarkable. Goodheart hypothesised that he had stimulated micro avulsed tendonattachments of the serratus as he palpated.(4) Kendall described the correct functionof the shoulder is dependant on the contraction and stability of the Serratus Anticus.(5)

Picture: Flared right scapula

Inhibition of this muscle, for whatever reason, will create difficulty raising theshoulder above the head as well as recruitment of adjacent muscles Trapezeii andLevator scapulae. Given the number of fasciculae that combine to contract thismuscle, there is little wonder that there may be a variety of strain injuries affecting itsfunction. Combinations of weight and duration of strain during normal lifting andreaching activities can soon overstretch and inhibit its function.(6)

Nijs, et al. describe these injuries as follows:

“The muscular system is the major contributor to scapular

positioning both at rest and during functional tasks. In the case of altered activity (delayed firing, inefficient recruitment, or increased tension and consequent shortening) of scapular muscles, scapular positioning is likely to become abnormal. Inappropriate control of scapular positioning has frequently been linked to shoulder and neck disorders.(6, 7, 8 and 9) Moreover, scientific evidence supporting abnormal scapular positioning in patients with shoulder impingement syndrome, 2 symptoms of shoulder impingement,(10 and 11) a traumatic shoulder instability,(12) multidirectional shoulder joint instability,(13) and shoulder pain after neck dissection in patients with cancer (14 and 15) is accumulating. One study has shown that physiotherapy (primarily exercise therapy targeting the scapulothoracic muscles) was superior over no treatment in patients with subacromial impingement syndrome. (16)” (7)The resulting pain can cascade into a variety of syndromes creating over-contractionof the supportive and antagonist muscles including pectoral, deltoid, rotator,clavicular and cervical groups. Rib elevation may be compromised causing medialstrain on the diaphragm and inferior strain on the abdominal muscles. This can thenresult in cardio-respiratory, digestive and back pain symptoms. It is not unusual forthe sufferer to be medically examined for heart problems, GERD, inflammatorydiseases, psychological or musculo skeletal pain.(8)

Normalising the inhibited serratus anticus can involve a variety of AK treatments

ranging from correcting the intervertebral foramina factors to fixing an hiatal herniasyndrome.(9) Keeping the muscle function normal in all movements may be a moredifficult challenge. Part of this process will involve assessing the integrity of theattachments of the origin as a base to work from.

Nijs, et al. further explain:

“Many strategies for the assessment of scapular positioning are

described in the scientific literature. However, most of these strategies apply expensive and specialized equipment (laboratory methods), making their applicability in clinical practice nearly impossible. From a clinical perspective, guidelines for a reliable and valid assessment of faulty scapular positioning in patients with shoulder pain are essentially lacking. There is a need to develop simple clinical indicators to allow clinicians to assess scapular kinematic behavior accurately.(2 and 5) These tests should be affordable, easy to perform, reliable, valid, and responsive to change.”(7)

MMT may provide the criteria to make this assessment in an inexpensive, efficientclinical manner. AK therapy options may provide similar efficient, inexpensivepatient compliant results.(10, 11)

CASE STUDY:

A 39 year old male, 183 cm and 120 kilo working as a railway signal man with a 16year history of occasional back pain that resolves with AK care attended the clinic inacute pain, graded at 9/10 on a numerical scale, complaining of difficulty breathing,difficulty standing erect and pain in the right mid back and rib area. He presentedantalgic to the right side, sweating and smelling of liniment. He said that he had beenfeeling fine since his last chiropractic check up 10 weeks prior. He said that 2 weeksearlier he felt slight pain in his right thigh, attended a medical physician and was toldit was a strain and not to worry about it. There was no history of imaging. The painleft a few days later. The patient explained that the problem began when he put on histrousers for work this morning (about 2 hours prior to his visit) and attempted to dothem up by tightening his belt. He said he felt something “give” in his back. Thepain doubled him up. His wife attempted to help by rubbing the pain area withliniment but it didn’t do much.Examination revealed normal reflexes for L2-S1. Digital pressure to the thoracicspine, lumbar spine or ribs produced no pain. Movement away from the side of painexacerbated the pain. Pain lessened as the patient contracted his body to the right. Novertigo, radicular pain or emotional distress was observed. Pain perception waslocated to the right serratus, rhomboid and abdominal region. Further investigationindicated restricted movement of the ribs on the right side with inspiration andexpiration indicating a diaphragm strain. T10-L2 were restricted with movement tothe right during motion palpation and were co incident with aggravating the pain.There was no indication of cyanosis. Manual muscle testing indicated inhibition ofthe right serratus anticus, spasm of the right rhomboid, inhibition of the right externalabdominus oblique and the diaphragm.(5)

Treatment began with a palliative discussion of the injury and its relevance. Manualtreatment began with the patient’s permission by the resolution of the diaphragmstrain with a compressive adjustment to the fundus of the stomach as described byWalther (9) resulting in a reduction of pain and deeper breath. TL and Challenge tothe proprioceptive reflexes of the attachments of the serratus anticus (as describedearlier in the paper) indicated a stimulus response at its lower attachment to theexternal abdominus oblique. Post MMT of the inhibited muscles indicatedstrengthening and improved support. The rhomboid pain self resolved followingserratus strengthening. The antalgic posture was still present when erect with painreturning when attempting to straighten. A right inhibited psoas was observed witherect MMT.

This responded to strain-counterstrain technique described by Jones (13) and SMT to

the fixation of T10-L2 using a traditional chiropractic side posture pull move. Reexamination in the erect posture indicated loss of acute pain, loss of antalgia, restoredmovement without restricted breathing. Slight pain remained on deep forcedinspiration, which appeared to be located at the transverse process and rib head of T8.This pain was positive to deep palpation of the rib head indicting probable ligamentinflammation. The patient perceived a change in pain to 5/10.(14)

Prognoses for his injury is positive with resolution complete in probably 3 days. Aday off work was advised and palliative care involving walking, prone lying and coldpacks during the day over the SA, EOA interdigitation. Supportive treatment within24 hours was scheduled in case of compensatory changes to the neuromusculoskeletalsystem of the patient.(15,16)

Consultation and examination the following day indicated the patient was back atwork with a subjective decrease in pain to 4/10. The patient was no longer antalgicand described his symptoms as a generalised stiffness with tightening of theabdominal and chest muscles. All muscles subjected to MMT on the previous visitwere strong with no signs of inhibition. Tendernous of the spinous processes of T12-L3 was observed. There was an indication for adjusting the L3 segment spinous rightusing challenge diagnoses. A side posture pull move with the patient lying on the rightside was the preferred adjustment. Challenge to the T4-8 indicated a need for fixationrelease using an anterior adjusting thrust. This was done using manual caudal tractionwith anterior pressure. A tapping challenge to the treated vertebrae indicated the needfor vibration. This was done using an Arthro-Stim instrument. Post pain evaluationafter treatment was 2/10. Follow up care was advised for the next day.Consultation for this 3rd visit indicated that the patient was completing full duties atwork. His subjective assessment of pain was for discomfort only with a 1/10 rating.Symptoms included slight low back stiffness with right thigh sensitivity to touch.MMT indicated that the original muscles had maintained their strength. No spinaltendernous was observed to digital pressure. Vertebral challenge of the whole spinewas completed with the patient in a prone position. C2&C7, T6-10, L5 Posterior andthe right 6th rib were indicted for subluxation adjustment. These were performedmanually in the prone position with drop technic. The patient’s subjective painperception after treatment was 0/10. Assessment for stability of care was scheduledfor one week.

A check up of all symptoms and findings was completed at one week and at onemonth. The patient had completed full work duties. No stiffness or pain wasobserved. MMT and vertebral examination failed to find any subluxation or muscleinhibition. Pain perception remained at 0/10.

The patient was advised to use elastic topped trousers to prevent further injury.TABLE 1 : Summary of key changes for this case

Anatomy Of The Serratus Anticus:

This is a thin muscular sheet also known as the serratus magnus, located between theribs and the scapula, spreading over the lateral part of the chest. It arises by fleshydigitations from the outer surfaces and superior borders of the first eight or nine ribs,and from the aponeuroses covering the intervening Intercostales. Each digitation(except the first) arises from the corresponding rib; the first springs from the first andsecond ribs and from the fascia covering the first intercostal space. From thisextensive attachment the fibres pass dorsalward, closely applied to the chest-wall, tothe vertebral border of the scapula, and are inserted into its ventral surface in thefollowing manner. The first digitation is inserted into a triangular area on the ventralsurface of the superior angle. The next two digitations spread out to form a thin,triangular sheet, the base of which is directed dorsal ward and is inserted into nearlythe whole length of the ventral surface of the vertebral border. The lower five or sixdigitations converge to form a fan shaped mass, the apex of which is inserted, bymuscular and tendinous fibres, into a triangular impression on the ventral surface ofthe inferior angle. The lower four slips interdigitate at their origins with theupper five slips of the Obliquus externus abdominis.(12)

Picture: Serratus and Abdominus junction

The long thoracic nerve from the brachial plexus, containing fibres from the fifth,sixth, and seventh cervical nerves innervate this muscle.

Function of the Serratus Anticus:

This muscle rotates the scapula, raising the point of the shoulder as in full flexion andabduction of the arm. It draws the scapula forward as in the act of pushing. Theupper digitation may draw the scapula downward and forward; the lower digitationsdraw the scapula downward. (12)

Dysfunction of the Serratus Anticus:

There is difficulty raising the arm in flexion, creating winging of the scapula. Withmarked weakness, the test position cannot be held. With moderate or slight weakness,the scapula cannot hold the position when pressure is applied on the arm. Because therhomboids are direct antagonists of the serratus, they can become shortened. Stabilityof the lower fasiculae of the serratus be compromised by inhibition of the ObliquusExternus abdominis.(5)

Diagnosing inhibition of the Serratus Anticus:

Strain, over stretching or micro avulsion of the tendons at the attachment of theSerratus Anticus and the Obliquus Externus abdominis may cause inhibition of the SAand the cascade of symptoms previously described.(4) 1. Test the muscle. Check that the shoulder flexors are strong before the test begins. Position the arm at 120 to 130o to stabilize the scapula in a position of abduction and lateral rotation, emphasize the upward rotation action of the serratus in the abducted position. 2. Have the patient therapy localise (TL) the fibers that interdigitate with the External Abdominus Oblique. 3. If the TL is positive and stimulates the inhibited Serratus Anticus the treatment is indicated. 4. Find the direction of treatment by using digital vectors along the length of both the serratus fasiculae and the abdominus attachment at the point of interdigitation that creates strengthening of the inhibited serratus anticus.

Treatment of the Serratus Anticus:

1. Use firm digital pressure in the direction of positive challenge or vibration.

2. Retest the muscle. Strengthening to the manual pressure of the MMT indicates a loss of inhibition.RESULTS:

The most common treatment for this condition after screening for pathology in themedical arena via accessing the ER or private medical service would be to use painmedication, anti inflammatory medication, advice to keep moving and restrictedactivity.

The patient’s presentation could have involved a number of approaches to care

ranging from disc injury due to the antalgia, to a cardio respiratory condition relatedto the breathing difficulties. The patient did not complain of a shoulder problem yetthe most obvious problem with this patient was restricted movement of the shoulder.All the symptoms during the first visit appeared related to the dysfunction of theshoulder and rib stabilizer muscles. It is possible the lateral thigh pain may have beena precursor for this acute injury given possible radiculopathy sourced at the fixation ofthe T10-L2 with probable hypermobility with the adjacent segment of L3.

Strain injuries of this kind usually heal with the resolution of inflammation andfunction. This case was no exception. The patient overstretched his shoulder and ribstabilizer muscles as he “did up” his pants. It is probable that the muscles may havebeen inhibited before the injury occurred given his history of previous back problems.The speed of use of the muscles may have been his undoing. They may not have beenable to contract as quickly as was required and overstretched. Speed of use can be acritical factor in the early morning when running late for work and the musclescoming out of a rest state from sleeping. Threats which may complicate this patientsrecovery included advising the patient to be careful with rapid movement in the first24 hours. Weight bearing aggravation of the injury can occur and will complicaterecovery and may create deeper underlying structural instability before ligamenthealing is complete.

The patients recovery from an acute pain and antalgic posture was remarkable in thathe was able to return to work with limited duties the day following the injury andreturn to full duty within 48 hours. The patient’s perception of pain was just asremarkable in that he showed a 50% improvement in loss of pain sequentially witheach of the treatments. The third treatment resulted in a complete loss of pain.

The change in treatment for each visit was also interesting. The first visit involvedacute pain management using MMT diagnoses and AK muscle reflex Treatments as amajor component of support to SMT of the thoracic region. The 2nd Visit focused onresolving upper lumbar pain most probably caused by ligament irritation. No muscleinhibition was observed on this visit. Yet the patient experienced “tightness” in hismid back. This resolution of lumbar pain and loss of “tightness” was achieved usingSMT for the involved vertebrae and adding vibration. The 3rd visit focused on theprobable pre existing condition of lumbar radiculopathy and less muscle stiffness.These symptoms resolved using SMT for the subluxations described.

It would seem that using the AK MMT approach to resolving the interdigitalfasciculae strain between the SA and OEA in this patient syndrome increased thepatient’s ability to recover quickly and return to work within 24 hours of the injury.More tradition SMT reduced symptoms from probable collateral injury during thenext 2 visits.

These findings are dependant on clinical observation and patient perception. Controlof the patient’s progress was voluntary with his own recognisance, which may havecompliance limitations.

CONCLUSION:

A closer study of the anatomy of the SA and the OEA illustrates an interdigitation thatmay be a location of a probable cause of SA inhibition. Rarely does a single muscleinhibit by itself. The case study presented is an example of the lateral diagnosticthinking necessary for quick resolution of acute disabling problems that patients cansuffer. Nostalgia for the roots of AK realised more information that may be useful inresolving problems related to injuries affected by difficult shoulder stability. The casestudy presented indicates the practical application of understanding the AK approachto treatment for this problem and its resolution. Further cases of mid back pain shouldbe examined for SA and OEA strain as a contributing factor.